Exploring Nitrogen Cycling in Lagos Lagoon, Nigeria: First Steps Towards an Integrated Monitoring Program

Abstract

Lagos lagoon, a critical coastal ecosystem in West Africa, faces escalating pollution threats from dense human habitation, yet lacks a coordinated water quality monitoring program. This study aimed to provide an integrated baseline of nutrient levels using stable isotope analyses of carbon (δ¹³C) and nitrogen (δ¹⁵N) in sediments, biota, and water. In Chapter 2, δ¹³C values were lower in freshwater-influenced zones and higher in marine-influenced areas, reflecting differences in carbon sources. δ¹⁵N showed predictable trophic enrichment, with minor seasonal effects. Baseline δ¹⁵N values were within the natural range of seawater and soil nitrate, complicating attribution of anthropogenic impacts. Chapter 3 compared nutrient analysis between Canadian and Nigerian labs, revealing discrepancies potentially due to procedural differences. These findings offer a baseline for future monitoring and highlight the need for standardized methods and international collaboration to improve nutrient measurement accuracy and reliability in Lagos lagoon.